How Does Earth’s Magnetic Field Change Solar Wind to a Gentle Breeze

Enveloping our planet and defending us from dangerous photo voltaic wind is an invisible magnetic discipline. Solar wind is a stream of plasma or charged particles like protons and electrons unleashed from the solar’s outer layers. Without magnetic discipline, photo voltaic wind may destroy our planet’s ambiance and make it inhabitable.

But precisely how the method works? For the primary time, researchers clarify how Earth’s magnetic discipline shoves apart the highly effective photo voltaic wind with none harm. As Earth strikes across the solar, it creates a bow-shaped wave or bow shock forward of itself, very like that in entrance of a transferring motorboat. When the electrons within the photo voltaic wind encounter the bow shock, their velocity is momentarily accelerated to such an extent that the electron stream turns into unstable and break down. This interplay slows down electrons and converts the power to warmth.

“If you were to stand on a mountaintop, you might get knocked over by a fast wind,” explained lead creator Li-Jen Chen from University of Maryland. “Fortunately, as the solar wind crashes into Earth’s magnetic field, the bow shock protects us by slowing down this wind and changing it to a nice, warm breeze. We now have a better idea how this happens.”

The discovering relies on knowledge collected by NASA’s Magnetospheric Multiscale (MMS) mission. The MMS mission consists of 4 equivalent satellites that research Earth’s magnetic discipline because it interacts with the photo voltaic wind and takes three-dimensional measurements each 30 milliseconds. The knowledge assist researchers higher perceive the position magnetic discipline performs round Earth.

“These extremely fast measurements from MMS allowed us finally to see the electron heating process in the thin shock layer,” mentioned co-author Thomas Moore from NASA’s Goddard Space Flight Center. “This is groundbreaking because now we have the ability to identify the mechanism at work, instead of just observing its consequences.”

During the mission, researchers noticed photo voltaic wind electron earlier than, throughout and after the encounter with bow shock and located that it took simply 90 milliseconds for bow shock to destabilize and break down electrons.

“The new observations of electron acceleration at the bow shock rewrite the current understanding of electron heating. For example, researchers didn’t expect that the bow shock could accelerate the solar wind electron stream to the speeds that we observed,” said Chen. “The study of electron heating is important not just for understanding how the bow shock protects Earth, but potentially for satellites, space travel and maybe exploring other planets in the future.”